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DOE Shines $21M on Advanced Lighting Research
coondoggie writes to mention that the US Department of Energy is planning to fork over close to $21 million for 13 projects promising to advance solid-state lighting research and development. "SSL lighting is an advanced technology that creates light with considerably less heat than incandescent and fluorescent lamps, allowing for increased energy efficiency. Unlike incandescent and fluorescent bulbs, SSL uses a semi-conducting material to convert electricity directly into light, which maximizes the light's energy efficiency, the DOE said in a release. Solid-state lighting encompasses a variety of light-producing semi-conductor devices, including light-emitting diodes (LEDs) and organic light-emitting diodes (OLEDs). "
OK, so the light is encrypted?
One would think that the government would encourage energy saving by ensuring cities weren't shining so much light up at the sky where it hardly does any good. I mean, just see Mizon's Light Pollution about not only how it has ruined astronomy, but how it's simply wasteful as well. But I imagine the energy lobby, who continues to fool the public into thinking that the more light street lamps produce the better, maintains its influence.
Do you use SSL lighting to illuminate an ATM machine that is connected to a VPN network?
'The tyrant will always find pretext for his tyranny.' - Aesop's Fables
I thought about this the last time I was flying across the country at night. "Why am *I*, at almost six miles up, able to see all these street lights and parking lots and malls and houses? What a waste of energy."
Seriously, we need to think about our light placement and usage.
I believe the luminous efficacy (lumens per watt, light per power invested) of solid state lamps still lags that for incandescents or arc lamps. So, I don't thing the "maximizes the light's efficiency" thing in the article is really accurate. SSL is great for neat things like integration into building materials, though. Or making traffic lights with a low probability of burning out.
There's even studies that show a lot of lighting does NOT deter crime. All it does is let the crook see what he's doing.
Don't get me wrong, any amount they can put into this research is a good thing, but on the scale of things compared to funds they put elsewhere, it seems rather low to me. This is an area that needs significant changes soon, but unfortunately it looks like we're going to get incremental adoption of more fluorescents first.
It's astonishing to me that the energy and environmental problems are so obvious, but so little effort is put into the solutions.
Where do I buy them now?
Do they fit into my regular sockets, including BR30 form factors?
Will they give me at least as much focused light?
How much do they cost?
How long do they last?
How much better than fluorescents?
Are they dimmable?
Are they protected against lightening strikes near by?
What toxic materials do they contain?
Will they let me adjust for the color balance I desire (a highly desirable feature)?
Who is exploited in their manufacture, and which country is getting all my money from them?
Going to a new lightening system is seldom as simple as unscrewing one and screwing in another. Many trade-offs exist.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
There are also studies linking light pollution to increases in breast cancer. On the face of it, might seem a little whacky, but basically the theory is, light at night causes decreased endogenous melatonin production (it doesn't take much light to cause a significant drop in melatonin production) Melatonin is a strong anti-oxidant that they theorize helps keep breast cancer in check. Anyway, that's the current theory to explain the studies.
LEDs are far more efficient than incandescent. I have an LED/incandescent flashlight that lasts far longer in LED mode than incandescent mode but is not quite as bright. ie. Led brightness * LED time far greater than incandescent brightness * incandescent time.
Engineering is the art of compromise.
LEDs might have heavy metals in them but this is well encapsulated and amortized over a far longer lifetime (100k hours vs 10k hours).
Engineering is the art of compromise.
Blacklight Power is a well-known combination of perpetual-motion and pyramid scams.
There are no good white basketball players...
Oh, sorry, I had a top secret flashback for a moment. White LEDs, iirc, are essentially fluorescent light sources which use the LED to stimulate emission in several bands based on the phosphors used. As such, they are still discrete (though not monochromatic) frequency lights and cannot creat and exact replica of incandescent (i.e. blackbody) radiation. I've not seen much on LED CRIs or color temps...most people are just so amazed that they produce "white" light that they don't seem to care. White LEDs, as a result of how they work, are only about 1/2 as efficient per watt as their more efficient monochromatic counterparts.
Is it just my observation, or are there way too many stupid people in the world?
Interesting. Do you have any references for properly lighting your home for maximum crime deterrence?
I have a streetlight right in front of my house, but have still had a couple minor criminal incidents.
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According to government data, only about 9% of the household electricity used in the United States is used for lighting. Most household electricity goes to refrigeration, water heating, air-conditioning, space heating, clothes drying, and so forth. That's why electricity usage spikes in the summer and in hot weather.
For that matter, only about 20% of our entire energy usage is represented by electricity, the rest being direct use of thermal energy (i.e. burning stuff like oil and gas) in factories, home heating furnaces, and in cars, trucks and railroad engines.
So overall the amount of our energy usage that goes to household lighting is 0.09 x 0.20 = about 2% of our total energy usage. If you manage to make lighting that is, say, 10 times more efficient than incandescent, then you will replace 2% with 0.2%, for a grand savings of 1.8%. Not impressive.
Are you suggesting that women need to expose their breasts to the light more often? Interesting...
I keep forgetting my place. Jesus is for losers. Why do I still play to the crowd?
And, no, LEDs are not fluorescent. Fluorescent bulbs stimulate mercury to emit UV light. The UV light hits the phosphorus which makes it fluoresce and produce visible light. LEDs work by jumping electrons across a band gap and a photon is emitted when it jumps back down. The high efficiency comes into play because it doesn't take much more energy than that of the band gap to make an electron jump.
:wq
Hmm... if you have trichromatic light of wavelengths 570nm, 540nm, and 430nm shining on an object that absorbs everything except 550nm, then the object will appear black won't it? Whereas if true white light were shining on it, it would reflect the 550nm wavelengths and our eye would interpret that as... yellow or something. Is that wrong?
*White* LEDs don't work that way. You might assume that white LEDs are simply three (or more) normal LEDs combined in a single package. While it is possible to make white LEDs this way, it's not the method usually used (for several reasons, including "color integrity").
Instead, white LEDs are typically made by coating a BLUE indium-gallium-nitride (InGaN) LED with phosphorous. This is not all that different from a fluorescent bulb, which is what the GP postulated.
Different color temperatures can be achieved by varying the phosphorous coverage. Lower coverage lets more blue through (cooler temperature), whereas higher coverage causes more blue to be absorbed and thus more of the phosphorous emission spectrum to be emitted. The dominant line in the most commonly used phosphorous for LEDs is around 580nm (yellow).
It's also possible to get white LEDs that are made by coating a near ultra-violet LED with phosphorous (thus getting even closer to the fluorescent bulb of the GP).
This might change in the future, with serious work being conducted in the field to improve on reliability, efficiency and color characteristics. To the best of my knowledge, however, none of the new methods (go search for yourself) are commercially available and as we all know, many things that seem promising in the lab never make it to market for any number of reasons.
For reference, red diodes emit at ~ 630nm, blue diodes at 470nm, green at 530nm. The exact wavelength of the emitted light depends on the materials used in the LED, of course.
Sure, right up until somebody steals it.
It's more often more about the perception of safety than actual safety, at least when it comes to crime. Lights leave shadows where objects block them. When your night vision adjusts to the light, the shadows, and anything in them, get proportionally dimmer to you, making it harder to see someone "lurking in the shadows".
There's a lot more we could do about night lighting. A hundred years ago, almost everyone lived in a Bortle scale 1 area. Now, almost nobody in the first world does, and even much of the third world has elevated Bortle limits. What percentage of Americans do you think have ever seen zodiacal light, gegenschein, shadows cast from Scorpius and Sagittarius, or had Jupiter and Venus affect their dark adaptation? It doesn't have to be this way. Some types of lights are subject to far less atmospheric scattering. Properly designed fixtures can eliminate most of the overhead glow and even give you more light for the areas you're trying to illuminate. And so on.
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